Phenylethanoids are a class of compounds reported to be present in plants like Cistanche deserticola and Bucldleja species (Quanbo Xing, Koji Hase et al, Planta Medica, 64, 120-125 (1998); Peter J. Houghton and Hiroshi Hikino. Planta Medica, Vol. 55, 123-126 (1989).
It is for the first time that a phenylethanoid—verbascoside (also called acteoside or kusaginin) has been isolated by the authors from Colebrookea oppositifolia and found to possess a very strong antihepatotoxic/hepatoprotective activity at unusually very low doses (between 1.25 and 2.5 mg/kg) in rats and mice.
The presence of number of flavonoids and glycoflavonoids has already been reported in the literature from Colebrookea oppositifolia [S. Aziz Ahmed, S. A. Siddiqui and Asif Zaman, Indian J. Chemistry 12 1327-28 (1974); S. A. Patwardhan and A. S. Gupta, Indian J. Chemistry, 20B, 627, (1981); Fan Yank, Xing-Li, HAN-Qing Wang and Chong-Ren Yang, Phytochemistry 42 , 867-69 (1996)]. However, the presence of Acteoside from this plant is being reported for the first time.
Antifertility activity of this plant in male rats with special reference to testicular cell population dynamics have earlier been reported (R. S. Gupta, R. J. Yadav, V. P. Dixit and M. P. Dobhal, Fitoterapia, 72, 236-45 (2001).
Though the Hepatoprotective/Antihepatotoxic activity of Acteoside (Verbascoside) isolated from other two plants viz. Cistanche species and Buddleja species has been reported. (Quanbo Xing, Koji Hase et al, Planta Medica, 64, 120-125 (1998); Peter J. Houghton and Hiroshi Hikino. Planta Medica, Vol. 55, 123-126 (1989), however the present invention not only reports a distinct source namely Colebrookea oppositifolia but the desired activity is accomplished at unusually very low dosage between 1.5 to 2.5 mg/kg in rats.
As already stated above the Hepatoprotective/Antihepatotoxic activity of acteoside has been reported both in vitro and in vivo (Quanbo Xing, Koji Hase et al, Planta Medica, 64, 120-125 (1998). But the present invention describes the isolation of acteoside from a hitherto unreported source in such a way that the compound shows antihepatotoxic/hepatoprotective activity at doses nearly 12 to 25 times lower than those already reported in the prior art (Quanbo Xing, Koji Hase et al, Planta Medica, 64, 120-125 (1998); Peter J. Houghton and Hiroshi Hikino. Planta Medica, Vol. 55, 123-126 (1989). Moreover the parameters evaluated in the prior reports are limited to ALT (in vivo) and AST & MDA (in vitro) whereas the present invention describes the influence of acteoside practically in all important parameters leading to for a clear decision on the efficacy of any hepatoprotective or antihepatotoxic product.
The reason for the activity of acteoside at such low doses compared to the one reported in the prior art may be due to the specific method of its isolation being distinct to yield a product of higher purity. Contaminants in phytochemicals are well documented to seriously jeopardize the activity of pure active compound though there could be synergistic action also of which, however, there in no mention or indication in the prior art.